Answer:
The principle of superposition states that the oldest sedimentary rock units are at the bottom, and the youngest are at the top. Based on this, layer C is oldest, followed by B and A.
Explanation:
A physical change because it is still water :)
Silicon because it is abundant on Earth. Also, carbon and silicon are both building blocks of life.
Answer:
[H⁺] = 5.012 x 10⁻⁹. & [OH⁻] = 1.995 x 10⁻⁶.
Explanation:
∵ pH = - log[H⁺]
8.3 = - log[H⁺]
∴ log[H⁺] = - 8.3.
<em>∴ [H⁺] = 5.012 x 10⁻⁹.</em>
∵ [H⁺][OH⁻] = 10⁻¹⁴.
<em>∴ [OH⁻] = 10⁻¹⁴/[H⁺] </em>= 10⁻¹⁴/(5.012 x 10⁻⁹) = <em>1.995 x 10⁻⁶.</em>